A. Field of the Invention PA1 B. Problems in the Art
The present invention relates to catheters, and in particular, to catheters utilized in investigative and therapeutic procedures with respect to the main coronary arteries of the heart.
The procedures involved with cardiac catheterization are well known in the art. Cardiac catheterization generally is used to investigate the condition of the main coronary arteries. The usual procedure is to utilize a long narrow flexible tubular catheter inserted into an artery either in the groin area or in the patient's arm. The catheter is moved up the artery and into the coronary arteries near the heart to inject x-ray dye (contrast media) into the coronary arteries to allow cardiologists to diagnose the existence or severity of coronary artery disease. Catheters can also be used as the conduits for guide wires for such things as dilatation balloons used in angioplasty. Other uses are possible.
The coronary arteries branch out from what is called the aortic arch. What are called ostia are the openings between the aortic arch and the left and right main coronary arteries. It is generally advantageous, and sometimes necessary, to be able to enter the ostia for these procedures.
One problem that exists with cardiac catheterization is that there are different sizes and shapes of aortic arches and different locations and distances between the aortic arch and the ostia for access to the coronary arteries. Therefore, the conventional solution in the art is to have available a number of differently sized and shaped catheters to allow the doctor to select essentially what is believed to be the best fit for a particular patient and organ configuration.
Different types of catheters are used or are preferred for different types of cardiac procedures. Furthermore, certain materials may be preferred for the catheters. Certain catheters are desired to be made of a more flexible material to allow more deformation, and therefore more flexibility as far as maneuvering and positioning the distal end of the catheter. On the other hand, more rigid, less flexible materials are desired by some to allow easier insertion through the long distance to the aortic arch. However, the less flexible materials are more difficult to conform to curves and bends, and run the risk of damage to the arteries or complications because of the nature of the material.
As can be appreciated, cardiac catheterization is not a trivial procedure. It requires the cardiologist to introduce the distal end of the catheter in an artery in the patient's limb (arm or leg) and then basically push the catheter up the artery to the aortic arch. Because of the limited ability to manipulate the tip once in the artery, the tip usually must have some sort of inherent configuration that would allow it to enter at least one coronary artery by simply pushing on the proximal but remotely located end. The inherent nature of the ostia into the coronary arteries is such that a straight ended catheter, while being fairly effective inserted through the limb arteries, does not function to effectively traverse the aortic arch and to enter the ostia.
No single catheter is known which allows easy and safe access to both ostia. Therefore, the state of the art is such that when investigation of one coronary artery is completed, the catheter has to be completely removed. A second catheter of a different shape is then inserted to investigate the second coronary artery. This is called catheter exchange. This greatly adds to the time, effort, and difficulty of these procedures, including risk associated with any such procedure.
It is therefore a principle object of the present invention to offer an improvement with respect to the problems, deficiencies, and needs in the art.
It is another object of the present invention to provide a cardiac catheter which can be used for both diagnostic and therapeutic cardiac procedures.
A further object of the present invention is to provide a cardiac catheter which can access both coronary ostia, including those with anatomically varied locations.
Another object of the present invention is to provide a cardiac catheter which may avoid the need for catheter exchange to access both ostia.
A still further object of the present invention is to provide a cardiac catheter which is stable in the sense that it can be inserted into a patient's limb artery and safely and efficiently moved to a location at or near the coronary ostia, and safely and effectively manipulated into the coronary ostia.
Another object of the present invention is to provide a catheter which is flexible enough to be manipulated as needed, and is safer than more inflexible designs.
These and other objects, features and advantages of the present invention will become more apparent with reference to the accompanying specification and claims.